Section 12 pasting: Bernoulli truncated sums #
Truncated type sums and their one-step recurrence: the counterpart of
MIPRE/Background/LIDT/MIPStarRE/LDT/Pasting/Bernoulli/TruncatedSums.lean in the port of
planning/c6b-plan.md (milestone M11, section "Port conventions").
No declaration of the vendored file reads a state. The algebraic identities (the one-bit
recurrences of the type monomials, their commutation with G and 1 - G, the binomial
expansion ∑_τ G^{|τ|} (1 - G)^{k - |τ|} = 1) hold in any ring, and the positivity facts in any
C*-algebra with its order, through CStarAlgebra.pow_nonneg and Commute.mul_nonneg in place
of the vendored Matrix.PosSemidef arguments, as in Co/Pasting/Sandwich/GHatSandwich.lean; so
they serve the local algebra 𝔓 and K →L[ℂ] K alike. The Hermitian clause of
truncatedTypeSumRecurrence is star T = T (the vendored Tᴴ = T), read off positivity.
The three type-weight identities of the vendored file are classical: this file imports the
vendored file and names them through an explicit open MIPStarRE.LDT.Pasting (…) list.
Not ported #
References #
In LionSR/MIPStarRE at commit 507e8122, not in this repository:
references/ldt-paper/ld-pasting.tex
Upstream keeps this helper private since its Lean-module port (LionSR/MIPStarRE at 5fc363b); the port carries its own copy, with upstream's proof.
Upstream keeps this helper private since its Lean-module port (LionSR/MIPStarRE at 5fc363b); the port carries its own copy, with upstream's proof.
Upstream keeps this helper private since its Lean-module port (LionSR/MIPStarRE at
5fc363b); the port carries its own copy, with upstream's proof.
Bernoulli recurrence weights #
Prepending a true bit multiplies the type monomial by G.
Prepending a false bit multiplies the type monomial by 1 - G.
Each Boolean-type monomial commutes with the base operator G.
Each Boolean-type monomial commutes with the complementary base operator 1 - G.
The truncated type sum commutes with the base operator G.
The truncated type sum commutes with the complementary base operator 1 - G.
The full sum of type operators equals the identity.
This is the commuting binomial expansion
∑ τ : GHatType k, G ^ |τ| * (1 - G) ^ (k - |τ|) = (G + (1 - G))^k = 1.
Each type monomial of a positive contraction is positive.
lem:truncated-type-sum-recurrence.
This records the Hermitian, positivity, boundedness, and one-step recurrence
properties of the truncated type sums used in the fromHToG reduction.